Field of the Invention
The present disclosure relates to a stemless humeral component of a shoulder joint prosthesis.
Description of the Related Art
In a shoulder joint, the head of the humerus interacts with the glenoid cavity of the scapula in a manner similar to a “ball and socket” joint. Over time, it may become necessary to replace the shoulder joint with a prosthetic shoulder joint including a humeral component.
Traditionally, the humeral component includes a humeral head and a stem. The stem is configured to be inserted into an intramedullary canal of the humerus. In certain cases, insertion of the stem disadvantageously requires bone to be removed to fit the stem to the canal due to patient-to-patient anatomical variation. Another disadvantage of this approach is that integration of the stem into the bone through a natural process of bone ingrowth can make it difficult to remove the humeral component if it becomes necessary to replace the humeral component with another device. Due to the length of the stem it can be required to remove a lot of bone to facilitate removal of the stem; this complicates the ability to anchor a revision stem into the remaining bone.
A stemless humeral component may be used to address some of the disadvantages of conventional humeral components. Stemless humeral components can decrease the amount of bone loss when preparing the humerus to receive the component and decrease the complexity of the joint replacement procedure. Stemless humeral component designs can be more challenging to secure to the humerus. Conventional stemless designs rely on bone ingrowth for retention in the humerus. While such designs perform well over time, there is a risk in the early days and weeks after surgery where such ingrowth has not yet occurred that the stemless humeral component will be dislodged from the humerus. Dislodgement may also occur due to excessive wear, forces applied thereto during a revision surgery or other high load conditions.